1311979 has 4 divisors (see below), whose sum is σ = 1319040. Its totient is φ = 1304920.

The previous prime is 1311971. The next prime is 1311991. The reversal of 1311979 is 9791131.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1311979 - 2³ = 1311971 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1311979.

It is not an unprimeable number, because it can be changed into a prime (1311971) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3244 + ... + 3625.

It is an arithmetic number, because the mean of its divisors is an integer number (329760).

2^1311979 is an apocalyptic number.

1311979 is a deficient number, since it is larger than the sum of its proper divisors (7061).

1311979 is an equidigital number, since it uses as much as digits as its factorization.

1311979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7060.

The product of its digits is 1701, while the sum is 31.

The square root of 1311979 is about 1145.4165181278. The cubic root of 1311979 is about 109.4734894086.

The spelling of 1311979 in words is "one million, three hundred eleven thousand, nine hundred seventy-nine".